DESCRIPTION

The
isfdtype()
function tests whether the file descriptor
fd
refers to a file of type
fdtype.
The
fdtype
argument specifies one of the
S_IF*
constants defined in
<sys/stat.h>
and documented in
stat(2)
(e.g.,
S_IFREG).

RETURN VALUE

The
isfdtype()
function returns 1 if the file descriptor
fd
is of type
fdtype
and 0 if it is not.
On error, -1 is returned and
errno
is set to indicate the cause.

ERRORS

The
isfdtype()
function can fail with any of the same errors as
fstat(3).

CONFORMING TO

The
isfdtype()
function is not specified in any standard,
but did appear in the draft POSIX.1g standard.
It is present on OpenBSD and Tru64 UNIX
(where the required header file in both cases is just
<sys/stat.h>,
as shown in the POSIX.1g draft),
and possibly other systems.

NOTES

SEE ALSO

COLOPHON

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